Use SPDX 3.0 license identifier

Use SPDX 3.0 license identifier

SPDX released version 3 of their license list (<https://spdx.org/licenses/>),
which changed the FSF licenses to explicitly end in -only or -or-later
instead of relying on an easy to miss + symbol.

Bug: T183858
Change-Id: I4cbb98ea2bbacf46a57401dbba2bdb076fca1d3a